The two collider experiments at the Tevatron, CDF and D0, have made a lot of progress in B{sub s} lifetime difference measurements. Here, they have included 3 different channels of measurements, namely, B{sub s} {yields} J/{psi} + {phi}, B{sub s} {yields} K{sup +}K{sup -} and B{sub s} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-}. Combining all the available measurements, they have obtained {Delta}{Lambda}{sub s} = 0.097{sub -0.042}{sup +0.041} ps{sup -1} and {bar {tau}} = 1/{Lambda}{sub s} = 1.461 {+-} 0.030 ps. {Delta}{Lambda}{sub s} is now 2.3 {sigma} away from zero.

The authors present recent results on b-hadron lifetimes and mixing obtained from the analysis of the data collected at the Tevatron Collider by the CDF and D0 Collaborations in the period 2002-2004. Many lifetime measurements have been updated since the Summer 2004 conferences, sometimes improving significantly the accuracy. Likewise the measurement of the B{sub d} oscillation frequency has been updated. New limits on the B{sub s} oscillation frequency have been determined using for the first time Run II data.

This 2nd edition is an extensive update of "B Decays?. The revisions are necessary because of the extensive amount of new data and new theoretical ideas. This book reviews what is known about b-quark decays and also looks at what can be learned in the future.The importance of this research area is increasing, as evidenced by the approval of the luminosity upgrade for CESR and the asymmetric B factories at SLAC and KEK, and the possibility of experiments at hadron colliders.The key experimental observations made thus far, measurement of the lifetimes of the different B species, B0-B0 mixing, the discovery of ?Penguin? mediated decays, and the extraction of the CKM matrix elements Vub and Vcb from semileptonic decays, as well as more mundane results, are described in great detail by the experimentalists who have been closely involved with making the measurements. Theoretical progress in understanding b-quark decays using HQET and lattice gauge techniques are described by theorists who have developed and used these techniques.Synthesizing the experimental and theoretical information, several articles discuss the implications for the ?Standard Model? and how further tests can be done using measurements of CP violation in the B system.

A measurement of b-hadron lifetimes in the fully reconstructed decay modes B 2!J/[psi]K+, B° 2!J/[psi]K*°, B° 2!J/[psi]K{sub S}°, and [Lambda]{sub b}° 2!J/[psi] [Lambda]° is reported using data corresponding to an integrated luminosity of 4.3 fb−1, collected by the CDF II detector at the Fermilab Tevatron. The measured values are [tau](B+) = 1.639 ± 0.009(stat) ± 0.009(syst) ps, [tau](B°) = 1.507 ± 0.010(stat) ± 0.008(syst) ps and [tau]([Lambda]{sub b}°) = 1.537 ± 0.045(stat) ± 0.014(syst) ps. The lifetime ratios are [tau](B+)/[tau](B°) - 1.088 ± 0.009(stat) ± 0.004(syst) and [tau]([Lambda]{sub b}°)/[tau](B°) = 1.020 ± 0.030(stat) ± 0.008(syst). These are the most precise measurements of these quantities from a single experiment. Observation is also reported for a structure near the J/[psi][phi] threshold, in B+ to J/[psi][phi]K+ decays with an integrated luminosity of 6.0 fb−1 and a statistical significance of 5 standard deviations. There are 19 ± 6 events observed for this structure at a mass of 4143.4{sub -3.0}{sup +2.9} ± 0.6 MeV/c2 and a width of 15.3{sub -6.1}{sup +10.4} ± 2.5 MeV/c2.